通过同转换分析识别玻璃老化的热障碍
Vasiliki Maria Stavropoulou1,2, Federico Caporaletti3, Florian Pabst3
1Centro de Física de Materiales (CSIC-UPV/EHU), Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain.
The journal of physical chemistry. B
|January 26, 2026
概括
玻璃老化需要改变热屏障. 最初的低障碍表明不同的机制,而后期阶段显示与α放松相关的障碍越来越大,揭示了复杂的玻璃老化动态.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 眼镜表现出老化,这是一个取决于时间的过程,其特性向平衡方向演变.
- 了解玻璃老化的动力学和机制对于预测材料的行为和稳定性至关重要.
- 热屏障控制了玻璃中的放松过程中分子重组的速度.
研究的目的:
- 为了研究玻璃老化过程中热屏障的时间依赖的变化.
- 探索衰老阶段与放松过程的激活能量之间的关系.
- 确定控制玻璃老化在不同平衡阶段的机制.
主要方法:
- 用同转换分析来研究依赖衰老的热屏障.
- 该方法应用于各种玻璃类型,包括小分子和聚合物.
- 激活能量被分析为放松进展的函数.
主要成果:
- 随着眼镜的老化和接近平衡,热屏障会增加.
- 在晚期的衰老阶段,激活障碍变得与α-放松相似.
- 在初始和中间老化阶段的低热障碍表明非α放松机制的参与.
结论:
- 玻璃老化的特点是不断演变的热屏障,在不同阶段运行着不同的机制.
- 只有在平衡的最后阶段,α-放松过程才成为主导.
- 玻璃老化的复杂性源于不同分子重组机制随时间的相互作用.
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